I'm driving mine through the winter in Wisconsin. I'm getting a set a blizzaks on my stock wheels, which are going to become my "winter set", and I'm using my 6uls with star spec tires for the summers. I got the luxury package, so I should be able to keep warm with the heated seat. I got an unlimited touchless carwash (with underbody flush) deal at a local gas station, so I'll be going through there a couple times a week to keep the salt off.
Having driven Miatas in the winter with snow tires for the past couple winters, trust me when I say that driving a rwd car in the snow is one of the most fun experiences you'll have with your car... especially when you have an LSD.
Enjoy!
Edit: Also don't forget to get some weathertech or similar floor mats to keep the winter crap from pooling on the floor.